Human Wave Demo—Modeling P & S waves in Solids & Liquids


How can I model P and S waves with my class?

This demonstration explores two of the four (P and S waves) main ways energy propagates from the hypocenter of an earthquake. In this kinesthetic demo, students "experience" the waves as they line up shoulder-to-shoulder to "become" the solid and then liquid material the waves travel through. The physical nature of the "Human wave" demonstration makes it a highly engaging activity for most students. Some find that this tactile/kinesthetic learning activity stretches them personally; while for others it channels disruptive energy into a creative endeavor. Either way, developing ways to physically involve students in learning helps students grasp, internalize and maintain abstract information. Once "performed," the principles of P and S waves will not be easily forgotten.

The Instructor Guide offers a simpler method than the video shown here, though graphs for the video method are included in the Guide.



  • An earthquake causes different types of energy to radiate from the epicenter
  • The P and S waves are the first two to arrive at any specific point
  • P waves and S waves have different motions and shake the earth differently as they travel through it
  • S waves do not travel through liquid
How can I get across the idea in a classroom activity using no props? The human wave is used as an analogy for travel times of P and S seismic waves.
This draft video uses arms over shoulders as well as hand holding methods, so read the caveats about the best method (arms over shoulders). 
Video Novice

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